CPUINFO(1)
## NAME
*cpuinfo* - display information about the processor(s) in use
## SYNOPSIS
*cpuinfo* \[-p port\]
## DESCRIPTION
The *cpuinfo* command displays available information about the processor.
The information displayed and the detail level is dependant upon the
processor itself, and what identication facilities are available.

For some processors such as the Z80 it is necessary to provide a suitable
I/O port for parts of the identification. For a Z80 system this should be a
port which can be written and reads back the same value while not having any
immediate side effect. The command will restore the port state.

## CPU BUGS AND FEATURES
The following 6502 series processor bugs are reported

:*brk*
  The brk instruction as an interrupt occurs loses the brk status
:*invread*
  Indexed addressing crossing a page boundary causes a spurious invalid read
:*jmpff*
  Certain indirect jumps use the wrong address
:*nobcd*
  The processor lacks BCD instructions
:*rmw*
  Read-modify-write instructions write back the original value then the new
  value
:*ror*
  The ror instruction does not work

The following 6502 features are reported

:*ai16*
  The processor supports 16bit accumulator and indexing modes
:*bcd*
  The processor supports the N V and Z flags in BCD mode
:*cmos*
  The processor is CMOS
:*nmos*
  The processor is NMOS

The following Z80 series processor bugs are reported

:*exaf*
  The ex af,af' instruction may behave incorrectly in some cases
:*iff*
  The interrupt status reporting is racy
:*inout*
  The in and out instructions may cause nearby jumps to misbehave
:*ldflag*
  The flags are not correctly updated on loads from I or R

## STANDARDS
cpuinfo is a Fuzix specific command
## AUTHOR
Written by Alan Cox
